It's something like a watch list, where the user can manage his watched/"to be watched" videos.

The watch list could not only show videos already watched, but also videos the user wants to watch in future.

This idea came to my mind when I was clicking through the website and discovered A LOT of interesting videos.

But they all can't be watched on one day and above all there is no chance to remember all them . So I wished that I could "store" them in a watch list where all videos that are interesting to me can be accessed and watched very fast without browsing the
whole website.

That's a good idea. Some kind of playlist of videos you want to watch when you have time. I currently store a small list in Evernote if I notice videos I want to watch, but currently don't have time. Because keeping this list and copying URLs is a bit clumsy,
I don't use it often.